Syngas, an extremely meaningful chemical feedstock consisting of hydrogen and carbon monoxide, can be produced through methane dry reforming with carbon dioxide. The extensively utilized Ni-based catalysts usually suffer from coke-induced instability. Herein, we design Ni-CeO_x bifunctional catalysts with different proximity and explore the influence of proximity level on anticoking performance. Ni-CeO_x bimetallic nanoparticles with intimate contact are precisely regulated through the anchoring strategy of coordination unsaturated Al³⁺_penta, which undergoes the topotactic exsolution of a Ni–Ce–O quasi-solid solution into Ni-CeO_x bimetallic nanoparticles. A trend toward easier elimination and even the absence of graphitic carbon is observed with a decreasing spatial distance between Ni and CeO_x, which is attributed to the proximity between the dissociation and gasification sites of CH_x* intermediates. CH_x* species generated at Ni nanoparticles migrated to adjacent CeO_x oxygen carriers for Ni-CeO_x/Al₂O₃ catalyst gasification with Ni-CeO_x bimetallic nanoparticle interfaces, which undergo the Mars–van Krevelen (MvK) mechanism. The exploration of the Ni-CeO_x proximity provides guidance for developing efficient and durable Ni-based DRM catalysts.

中文翻译：

---

稳定活性氧化铝上的 Ni-CeOx 双功能纳米颗粒以增强甲烷干重整的碳阻力


合成气是一种由氢气和一氧化碳组成的极其有意义的化学原料，可以通过甲烷与二氧化碳的干重整来生产。广泛使用的镍基催化剂通常会出现焦炭引起的不稳定性。在此，我们设计了具有不同接近度的 Ni-CeO_x 双功能催化剂，并探讨了接近度对防焦性能的影响。紧密接触的 Ni-CeO_x 双金属纳米颗粒通过配位不饱和 Al³⁺_penta 的锚定策略进行精确调节，该策略经历 Ni-Ce-O 准固溶体拓扑溶出到 Ni-CeO_x 双金属纳米颗粒中。随着 Ni 和 CeO_x 之间的空间距离减小，观察到更容易消除甚至不存在石墨碳的趋势，这归因于 CH_x* 中间体的解离和气化位点之间的接近。在 Ni 纳米颗粒上生成的 CH_x* 物质迁移到相邻的 CeO_x 氧载体上，用于 Ni-CeO_x/Al₂O₃ 催化剂气化与 Ni-CeO_x 双金属纳米颗粒界面，其经历 Mars-van Krevelen （MvK） 机制。对 Ni-CeO_x 邻近度的探索为开发高效耐用的 Ni 基 DRM 催化剂提供了指导。